Pricing

Start free with 100 calculations a month. Every plan has every endpoint and every tax year.

Free

£0 no card

Included
100 calculations a month
Then
Stops until next month (402, with an upgrade link)
Rate limit
5 a second

Pro

£14 a month

Included
5,000 calculations a month
Then
£4 per 1,000 more
Rate limit
20 a second

Scale

£49 a month

Included
50,000 calculations a month
Then
£2 per 1,000 more
Rate limit
50 a second

Enterprise

Custom invoiced

Included
Your volume
Then
Agreed with you
Rate limit
Agreed, with an SLA

Questions

What counts as a calculation?

One successful call to any endpoint that needs a key: a take-home, an employer cost, a payroll period, a statutory payment and so on. Calls refused for bad input are not counted, and reference data (rates, tax years, tax codes) is free.

Do plans limit which endpoints I can use?

No. Every plan has every endpoint and every tax year; plans differ only in volume and rate limit.

What happens when the free plan’s 100 are used up?

Calls return 402 with a link to upgrade until the next month. Paid plans never stop: calculations past the plan’s allowance are billed as extra, in arrears.

Is there a sandbox?

The free plan is the sandbox: a calculation costs nothing to serve and touches no one’s data, so every key gets real answers from its first call.

Get an API key

Free to start, with every endpoint.